In 1974, Robert Charleston had the following to say in the summary of his article on “Glass in Persia in the Safavid Period and Later”:

“The time is not yet ripe for a final judgment on the nature of the glasses manufactured in Persia from the late 16th to the 19th century, and the present essay is no more than an attempt to lay a foundation on hich further work in this field may rest. It is greatly to be hoped that systematic excavation in Iran will one day provide the basis for a firm chronology.“

Sadly, almost 40 years have passed, and really, little more has been proven. Charleston was correct; questions will remain until the time when archaeological evidence proves that this glass existed in certain time periods, not in others, and until we can see transitions in construction type (if they indeed exist) in glass that has been found in situ in clearly dateable layers.